1. Field of Invention
The present invention relates to a process for laminating a wood veneer to a gypsum board or drywall and impressing or debossing decorative patterns or designs into the wood veneer laminated gypsum board or drywall and relates to the product formed by the process.
2. Background of the Prior Invention
Several techniques have been proposed in the prior art for impressing or debossing decorative designs directly into gypsum board. Examples of the prior art techniques are disclosed in U.S. Pat. Nos. 1,871,843 and 1,943,663 to Ericson, 2,803,188 to Duvall, 3,630,817 to Winkowski, 4,007,076 to Clarke et al., 4,073,230 to Akerson, and 4,608,108 to Goll; and Great Britain Patent Publication No. 1,012,254.
More specifically, in one prior art technique, decorative impressions are debossed into the board while the core gypsum material is still in a plastic state during its initial manufacture as disclosed, for example, in U.S. Pat. Nos. 1,943,663 to Ericson and 4,608,108 to Goll. Experiences indicate that this technique is difficult to control because the core gypsum material hardens unevenly.
In another prior art technique a board or like material is debossed by wetting the board with a vaporized or vaporizable liquid agent such as steam or water or water soluble wetting solution and then heatpressing the wet board for a predetermined time, as disclosed, for example, in U.S. Pat. Nos. 1,871,843 to Ericson, 2,803,188 to Duvall, 4,007,076 to Clarke et al, and 4,073,230 to Akerson. In such a process, the steam or the water, which vaporizes into steam when heated during the debossing stage, is designed to enter the pores of the paper coat of the gypsum board and to plasticize its interior. The plasticization of the board permits decorative patterns to be debossed.
In another prior technique, an outer paperlike covering layer of a gypsum board is lightly debossed with a heated press without using steam or water, as disclosed in U.S. Pat. No. 4,110,507 to Colledge. A decorative pattern of wood grain is formed on the outer covering layer.
Yet in another prior technique, a water barrier layer of an acrylic film or the like material is formed on the board. Printing designs are debossed into the film covered board prior to the film fully setting as disclosed, for example, in U.S. Pat. Nos 3,630,817 to Winkowski.
Laminating a wood veneer and the like to a board or pre-debossed board, such as plywood and chip board and the like, is known, as disclosed, for example, in U.S. Pat. Nos. 4,853,062 to Gartland, 4,812,188 to Hansen, 4,844,968 to Persson et al., 4,142,007 to Lampe et al, and 3,846,219 and 3,793,125 to Kunz.
A use of a metallic foil as a separation layer in a laminated board is also disclosed, for example, in U.S. Pat. Nos. 3,793,125 to Kunz, and 4,153,490 to Werz et al. It is also known to bond an aluminum overlay with a wooden product before shaping the wooden product with a press, as disclosed, for example, in U.S. Pat. No. 3,480,501 to Burch.
None of these prior inventions, however, disclose a process for debossing a decorative wood veneer laminated gypsum board with printing designs; nor do they disclose a debossed wood veneer laminated gypsum board. Furthermore, none of these prior inventions disclose the use of a metallic layer between the wood veneer and the gypsum board to enable the wood veneer to be debossed without damaging the wood veneer during the debossing stage.